scholarly journals Human Type 3 3α-Hydroxysteroid Dehydrogenase (Aldo-Keto Reductase 1C2) and Androgen Metabolism in Prostate Cells

Endocrinology ◽  
2003 ◽  
Vol 144 (7) ◽  
pp. 2922-2932 ◽  
Author(s):  
Tea Lanišnik Rižner ◽  
Hsueh K. Lin ◽  
Donna M. Peehl ◽  
Stephan Steckelbroeck ◽  
David R. Bauman ◽  
...  
Keyword(s):  
Primary Cultures ◽  
Hydroxysteroid Dehydrogenase ◽  
Product Inhibition ◽  
High Rate ◽  
Retinol Dehydrogenase ◽  
Normal Prostate ◽  
Androgen Metabolism ◽  
Prostate Cells ◽  
In Cells

Abstract Human aldo-keto reductases (AKRs) of the AKR1C subfamily function in vitro as 3-keto-, 17-keto-, and 20-ketosteroid reductases or as 3α-, 17β-, and 20α-hydroxysteroid oxidases. These AKRs can convert potent sex hormones (androgens, estrogens, and progestins) into their cognate inactive metabolites or vice versa. By controlling local ligand concentration AKRs may regulate steroid hormone action at the prereceptor level. AKR1C2 is expressed in prostate, and in vitro it will catalyze the nicotinamide adenine dinucleotide (NAD+)-dependent oxidation of 3α-androstanediol (3α-diol) to 5α-dihydrotestosterone (5α-DHT). This reaction is potently inhibited by reduced NAD phosphate (NADPH), indicating that the NAD+: NADPH ratio in cells will determine whether AKR1C2 makes 5α-DHT. In transient COS-1-AKR1C2 and in stable PC-3-AKR1C2 transfectants, 5α-DHT was reduced by AKR1C2. However, the transfected AKR1C2 oxidase activity was insufficient to surmount the endogenous 17β-hydroxysteroid dehydrogenase (17β-HSD) activity, which eliminated 3α-diol as androsterone. PC-3 cells expressed retinol dehydrogenase/3α-HSD and 11-cis-retinol dehydrogenase, but these endogenous enzymes did not oxidize 3α-diol to 5α-DHT. In stable LNCaP-AKR1C2 transfectants, AKR1C2 did not alter androgen metabolism due to a high rate of glucuronidation. In primary cultures of epithelial cells, high levels of AKR1C2 transcripts were detected in prostate cancer, but not in cells from normal prostate. Thus, in prostate cells AKR1C2 acts as a 3-ketosteroid reductase to eliminate 5α-DHT and prevents activation of the androgen receptor. AKR1C2 does not act as an oxidase due to either potent product inhibition by NADPH or because it cannot surmount the oxidative 17β-HSD present. Neither AKR1C2, retinol dehydrogenase/3α-HSD nor 11-cis-retinol dehydrogenase is a source of 5α-DHT in PC-3 cells.

Expression of Distinct α Subunits of GABAA Receptor Regulates Inhibitory Synaptic Strength

2004 ◽  
Vol 92 (3) ◽  
pp. 1718-1727 ◽  
Author(s):  
Pavel I. Ortinski ◽  
Congyi Lu ◽  
Kentaroh Takagaki ◽  
Zhanyan Fu ◽  
Stefano Vicini
Keyword(s):  
Primary Cultures ◽  
Molecular Assembly ◽  
Inhibitory Synapses ◽  
Critical Determinant ◽  
Pharmacological Agents ◽  
Α Subunit ◽  
Subunit Expression ◽  
Α Subunits ◽  
In Cells

Distinct α subunit subtypes in the molecular assembly of GABAA receptors are a critical determinant of the functional properties of inhibitory synapses and their modulation by a range of pharmacological agents. We investigated the contribution of these subunits to the developmental changes of inhibitory synapses in cerebellar granule neurons in primary cultures from wild-type and α1 subunit −/− mice. The decay time of miniature inhibitory postsynaptic currents (mIPSCs) halved between 6 days in vitro (DIV6) and DIV12. This was paralleled by the decrease of α2 and α3 subunits, the increase of α1 and α6 subunits expression at synapses, and changes in the action of selective α subunit modulators. A small but significant shortening of mIPSCs was observed with development in cells from −/− mice together with a decrease in the expression of α3 subunit. In contrast, the expression of α2 subunit at inhibitory synapses in −/− cells was significantly higher than in +/+ cells at DIV11-12. α5 subunit was not detected, and increased sensitivity to a selective α4/α6 subunit agonist suggests increased expression of extrasynaptic receptors in −/− mice. β2/β3 subunit expression and loreclezole sensitivity increased with development in +/+ but not in −/− cells, supporting the preferential association of the α1 with the β2 subunit. Synaptic charge transfer strongly decreased with development but was not different between cells in the +/+ and −/− groups until DIV11-12. Our results uncover a pattern of sequential expression of α subunits underlying the changes in functional efficacy of GABAergic networks with development.

scholarly journals Modulation of 11β-Hydroxysteroid Dehydrogenase Isozymes by Growth Hormone and Insulin-Like Growth Factor: In Vivo and In Vitro Studies1

1999 ◽  
Vol 84 (11) ◽  
pp. 4172-4177 ◽  
Author(s):  
J. S. Moore ◽  
J. P. Monson ◽  
G. Kaltsas ◽  
P. Putignano ◽  
P. J. Wood ◽  
...  
Keyword(s):  
Growth Factor ◽  
Reductase Activity ◽  
Primary Cultures ◽  
Inverse Correlation ◽  
Hydroxysteroid Dehydrogenase ◽  
Insulin Like Growth Factor ◽  
Igf I ◽  
Glucose Output

The interconversion of hormonally active cortisol (F) and inactive cortisone (E) is catalyzed by two isozymes of 11β-hydroxysteroid dehydrogenase (11βHSD), an oxo-reductase converting E to F (11βHSD1) and a dehydrogenase (11βHSD2) converting F to E. 11βHSD1 is important in mediating glucocorticoid-regulated glucose homeostasis and regional adipocyte differentiation. Earlier studies conducted with GH-deficient subjects treated with replacement GH suggested that GH may modulate 11βHSD1 activity. In 7 acromegalic subjects withdrawing from medical therapy (Sandostatin-LAR; 20–40 mg/month for at least 12 months), GH rose from 7.1 ± 1.5 to 17.5 ± 4.3 mU/L (mean ± se), and insulin-like growth factor I (IGF-I) rose from 43.0 ± 8.8 to 82.1 ± 13.7 nmol/L (both P < 0.05) 4 months after treatment. There was a significant alteration in the normal set-point of F to E interconversion toward E. The fall in the urinary tetrahydrocortisols/tetrahydocortisone ratio (THF+allo-THF/THE; 0.82 ± 0.06 to 0.60 ± 0.06; P < 0.02) but unaltered urinary free F/urinary free E ratio (a marker for 11βHSD2 activity) suggested that this was due to inhibition of 11βHSD1 activity. An inverse correlation between GH and the THF+allo-THF/THE ratio was observed (r = −0.422; P < 0.05). Conversely, in 12 acromegalic patients treated by transsphenoidal surgery (GH falling from 124 ± 49.2 to 29.3 ± 15.4 mU/L; P < 0.01), the THF+allo-THF/THE ratio rose from 0.53 ± 0.06 to 0.63 ± 0.07 (P < 0.05). Patients from either group who failed to demonstrate a change in GH levels showed no change in the THF+allo-THF/THE ratio. In vitro studies conducted on cells stably transfected with either the human 11βHSD1 or 11βHSD2 complementary DNA and primary cultures of human omental adipose stromal cells expressing only the 11βHSD1 isozyme indicated a dose-dependent inhibition of 11βHSD1 oxo-reductase activity with IGF-I, but not GH. Neither IGF-I nor GH had any effect on 11βHSD2 activity. GH, through an IGF-I-mediated effect, inhibits 11βHSD1 activity. This reduction in E to F conversion will increase the MCR of F, and care should be taken to monitor the adequacy of function of the hypothalamo-pituitary-adrenal axis in acromegalic subjects and in GH-deficient, hypopituitary patients commencing replacement GH therapy. Conversely, enhanced E to F conversion occurs with a reduction in GH levels; in liver and adipose tissue this would result in increased hepatic glucose output and visceral adiposity, suggesting that part of the phenotype currently attributable to adult GH deficiency may be an indirect consequence of its effect on tissue F metabolism via 11βHSD1 expression.

scholarly journals Synthesis, Characterisation and In Vitro Anticancer Activity of Catalytically Active Indole-Based Half-Sandwich Complexes

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4540
Author(s):  
Joan J. Soldevila-Barreda ◽  
Kehinde B. Fawibe ◽  
Maria Azmanova ◽  
Laia Rafols ◽  
Anaïs Pitto-Barry ◽  
...  
Keyword(s):  
Sodium Formate ◽  
In Vitro Cytotoxicity ◽  
High Turnover ◽  
Normal Prostate ◽  
Prostate Cell ◽  
Ovarian Cancer Cell Lines ◽  
Catalytically Active ◽  
Half Sandwich ◽  
In Cells

The synthesis, characterisation and evaluation of the in vitro cytotoxicity of four indole-based half-sandwich metal complexes towards two ovarian cancer cell lines (A2780 and A2780cisR) and one normal prostate cell line (PNT2) are presented herein. Although capable of inducing catalytic oxidation of NADH and able to reduce NAD+ with high turnover frequencies, in cells and in the presence of sodium formate, these complexes also strongly interact with biomolecules such as glutathione. This work highlights that efficient out-of-cells catalytic activity might lead to higher reactivity towards biomolecules, thus inhibiting the in-cells catalytic processes.

ANDROGEN METABOLISM IN THE VENTRAL SEBACEOUS GLAND PATCH OF THE MONGOLIAN GERBIL

1973 ◽  
Vol 59 (3) ◽  
pp. 487-493 ◽  
Author(s):  
M. B. HODGINS ◽  
J. B. HAY
Keyword(s):  
Mongolian Gerbil ◽  
Enzyme Activities ◽  
Sebaceous Gland ◽  
Hydroxysteroid Dehydrogenase ◽  
Rat Skin ◽  
Androgen Metabolism

SUMMARY The metabolism of [7α-3H]dehydroepiandrosterone (DHA), [7α-3H]-androstenedione and [7α-3H]testosterone was studied in the ventral sebaceous gland patch of the Mongolian gerbil in vitro. The main enzyme activities found were 17β-hydroxysteroid dehydrogenase, 5α-reductase, 17α-hydroxysteroid dehydrogenase, 3α-hydroxysteroid dehydrogenase, sulphotransferase and hydroxylase. The active androgen 5α-dihydrotestosterone was formed in appreciable amounts from both testosterone and androstenedione. The 17β-hydroxysteroid dehydrogenase actively formed both 17-oxo and 17β-hydroxysteroids in this tissue. The conversion of DHA to C4–5 unsaturated steroids and 5α-steroids was not observed presumably due to a lack of 3β-hydroxysteroid dehydrogenase Δ4–5isomerase. The metabolism was compared with that in human and rat skin and its significance discussed.

scholarly journals In Vitro Analysis of Deoxynivalenol Influence on Steroidogenesis in Prostate

Toxins ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 685
Author(s):  
Kinga Anna Urbanek ◽  
Karolina Kowalska ◽  
Dominika Ewa Habrowska-Górczyńska ◽  
Kamila Domińska ◽  
Agata Sakowicz ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Fusarium Species ◽  
Male Rats ◽  
Trichothecene Mycotoxin ◽  
Normal Prostate ◽  
Prostate Cells ◽  
Expression Of Genes ◽  
Food And Feed ◽  
Vitro Analysis

Deoxynivalenol (DON) is a type-B trichothecene mycotoxin produced by Fusarium species, reported to be the most common mycotoxin present in food and feed products. DON is known to affect the production of testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH) in male rats, consequently affecting reproductive endpoints. Our previous study showed that DON induces oxidative stress in prostate cancer (PCa) cells, however the effect of DON on the intratumor steroidogenesis in PCa and normal prostate cells was not investigated. In this study human normal (PNT1A) and prostate cancer cell lines with different hormonal sensitivity (PC-3, DU-145, LNCaP) were exposed to DON treatment alone or in combination with dehydroepiandrosterone (DHEA) for 48 h. The results of the study demonstrated that exposure to DON alone or in combination with DHEA had a stimulatory effect on the release of estradiol and testosterone and also affected progesterone secretion. Moreover, significant changes were observed in the expression of genes related to steroidogenesis. Taken together, these results indicate that DON might affect the process of steroidogenesis in the prostate, demonstrating potential reproductive effects in humans.

scholarly journals Increased expression of type 2 3α-hydroxysteroid dehydrogenase/type 5 17β-hydroxysteroid dehydrogenase (AKR1C3) and its relationship with androgen receptor in prostate carcinoma

2006 ◽  
Vol 13 (1) ◽  
pp. 169-180 ◽  
Author(s):  
K-M Fung ◽  
E N S Samara ◽  
C Wong ◽  
A Metwalli ◽  
R Krlin ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Androgen Receptor ◽  
Epithelial Cells ◽  
Prostate Carcinoma ◽  
Primary Cultures ◽  
Hydroxysteroid Dehydrogenase ◽  
Human Prostate ◽  
Normal Prostate ◽  
Prostate Epithelial Cells

Type 2 3α-hydroxysteroid dehydrogenase (3α-HSD) is a multi-functional enzyme that possesses 3α-, 17β- and 20α-HSD, as well as prostaglandin (PG) F synthase activities and catalyzes androgen, estrogen, progestin and PG metabolism. Type 2 3α-HSD was cloned from human prostate, is a member of the aldo-keto reductase (AKR) superfamily and was named AKR1C3. In androgen target tissues such as the prostate, AKR1C3 catalyzes the conversion of Δ4-androstene-3,17-dione to testosterone, 5α-dihydrotestosterone to 5α-androstane-3α,17β-diol (3α-diol), and 3α-diol to androsterone. Thus AKR1C3 may regulate the balance of androgens and hence trans-activation of the androgen receptor in these tissues. Tissue distribution studies indicate that AKR1C3 transcripts are highly expressed in human prostate. To measure AKR1C3 protein expression and its distribution in the prostate, we raised a monoclonal antibody specifically recognizing AKR1C3. This antibody allowed us to distinguish AKR1C3 from other AKR1C family members in human tissues. Immunoblot analysis showed that this monoclonal antibody binds to one species of protein in primary cultures of prostate epithelial cells and in LNCaP prostate cancer cells. Immunohistochemistry with this antibody on human prostate detected strong nuclear immunoreactivity in normal stromal and smooth muscle cells, perineurial cells, urothelial (transitional) cells, and endothelial cells. Normal prostate epithelial cells were only faintly immunoreactive or negative. Positive immunoreactivity was demonstrated in primary prostatic adenocarcinoma in 9 of 11 cases. Variable increases in immunoreactivity for AKR1C3 was also demonstrated in non-neoplastic changes in the prostate including chronic inflammation, atrophy and urothelial (transitional) cell metaplasia. We conclude that elevated expression of AKR1C3 is highly associated with prostate carcinoma. Although the biological significance of elevated AKR1C3 in prostatic carcinoma is uncertain, AKR1C3 may be responsible for the trophic effects of androgens and/or PGs on prostatic epithelial cells.

scholarly journals Genotoxicity and cytotoxicity of sevoflurane in two human cell lines in vitro with ionizing radiation

2014 ◽  
pp. 104-109
Author(s):  
Miguel Alcaraz ◽  
Samuel Quesada ◽  
David Armero ◽  
Rocio Martín-Gil ◽  
Amparo Olivares ◽  
...  
Keyword(s):  
Micronucleus Test ◽  
Human Lymphocytes ◽  
In Vitro Toxicity ◽  
X Rays ◽  
Normal Prostate ◽  
Cytotoxic Effects ◽  
Prostate Cells ◽  
Dose Dependent ◽  
Different Doses

Objective: To determine the in vitro toxicity of different concentrations of sevoflurane in cells exposed to X-ray. Methods: The genotoxic effects of sevofluorane were studied by means of the micronucleus test in cytokinesis-blocked cells of irradiated human lymphocytes. Subsequently, its cytotoxic effects on PNT2 (normal prostate) cells was determined using the cell viability test (MTT) and compared with those induced by different doses of X-rays. Results: A dose- and time-dependent cytotoxic effect of sevofluorane on PNT2 cells was determined (p> 0.001) and a dose-dependent genotoxic effect of sevofluorane was established (p> 0.001). Hovewer, at volumes lower than 30 μL of sevofluorane at 100%, a non-toxic effect on PNT2 cells was shown. Conclusion: Sevofluorane demonstrates a genotoxic capacity as determined in vitro by micronucleus test in cytokinesis-blocked cells of irradiated human lymphocytes.

Cell-matrix interaction in bone: type I collagen modulates signal transduction in osteoblast-like cells

1995 ◽  
Vol 268 (5) ◽  
pp. C1090-C1103 ◽  
Author(s):  
J. Green ◽  
S. Schotland ◽  
D. J. Stauber ◽  
C. R. Kleeman ◽  
T. L. Clemens
Keyword(s):  
Signal Transduction ◽  
Signaling Pathways ◽  
Type I Collagen ◽  
Primary Cultures ◽  
Neonatal Rat ◽  
Type I ◽  
Osteosarcoma Cell ◽  
Umr 106 ◽  
In Cells

Cell interaction with extracellular matrix (ECM) modulates cell growth and differentiation. By using in vitro culture systems, we tested the effect of type I collagen (Coll-I) on signal transduction mechanisms in the osteosarcoma cell line UMR-106 and in primary cultures from neonatal rat calvariae. Cells were cultured for 72 h on Coll-I gel matrix and compared with control cells plated on plastic surfaces. Agonist-dependent and voltage-dependent rises in cytosolic Ca2+ concentration ([Ca2+]i; measured by fura 2 fluorometry) were significantly blunted in cells cultured on Coll-I compared with cells grown on plastic. In UMR-106 cells, the collagen matrix effect was mimicked by 24-h incubation with soluble Coll-I or short peptides containing the arginine-glycine-aspartate motif. Accumulation of cellular adenosine 3',5'-cyclic monophosphate (cAMP) stimulated by parathyroid hormone, cholera toxin, and forskolin was augmented (50-150%) in cells plated on Coll-I vs. control. The collagen effect on both [Ca2+]i- and adenylate cyclase-signaling pathways in UMR-106 cells was abrogated in the presence of protein kinase C (PKC) depletion or inhibition. Also, Coll-I induced a twofold increase in membrane-bound PKC without changing cytosolic PKC activity. Thus, by altering PKC activity, Coll-I modulates the [Ca2+]i- and cAMP-signaling pathways in osteoblasts. This, in turn, may influence bone remodeling processes.

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